The present invention relates to a process of connecting and removing a rotatable mounting disk having holders for vehicle wheel rims in the mounting and removing of tires. The mounting disk connects with a tire mounting device having a rotatable pin. The rotatable mounting disk with holders functions to secure vehicle wheel rims for mounting and removing tires.
The brochure called "Mounting Tires with State of the Art Schenck A-S-G-Technology" published in April of 1991 by Schenck Auto-Service-Gerate GmnH discloses a tire mounting device having radially sliding and pneumatically activated holders on a rotatable mounting disk. In order to mount a tire onto a vehicle wheel rim, these holders grap one side of the wheel rim at its wheel flange and hold the wheel rim in such a way as to be self-centering so that, using a mounting head located on a mounting arm, one side of the tire can be placed behind the freely rotating wheel flange during the mounting. After the halfway-mounted tire has been turned and the wheel rim has once again been clamped by means of the holders, the other side of the tire can likewise by completely mounted onto the wheel rim behind the wheel flange. The wheel flange is then free by means of the mounting head by rotating the rotatable disk with respect to the stationary mounting head. Subsequently, the holders securing the rim onto the wheel flange are loosened so that the compeltely mounted wheel can be removed from the tire mounting device and the tire can be filled with the correct amount of operating air pressure. When the tire is removed from the wheel rim in the opposite order, one side of the tire is first removed and then the other side of the tire is lifted over the corresponding rotating wheel flange and then released. Such tire mounting devices can always be used and are suitable for steel wheel rims. However, when the rims have a large wheel flange diameter, these devices become quite complex since holders or clamping jaws--which are pneumatically activated for the most part --can constitute a hindrance during mounting and removal of the tires since they extend over the mounting disk. Unlimited enlargement of the mounting disk can only be carried out with great difficultly. For this reason, mounting and removal devices have already been designed for large truck tires in which the axis of the mounting disk on the tire mounting device is not positioned in a vertical direction but rather in a horizontal direction.
If wheel rims made of light-metal alloys--optionally polished and coated--are used instead of steel wheel rims, and if tires with a low cross section are mounted onto these wheel rims, the forces exerted on the rotating wheel flanges are considerably increased particularly when the width of the wheel rim is increased. This leads to a substantial rise in contact pressure. Moreover, there is also a risk that, due to the smooth surface of the wheel rim, the clamped wheel rim may slip awy from the clamping jaws. This occurs because the forces exerted by the mounting head during the mounting of the tire over the freely rotating wheel flange are briefly too great. Thus, damage to or destruction of the expensive wheel rim cannot be ruled out. Similar problems occur with such wheel rims made of light-metal alloys which are cast or forged, even if the clamping is carried out from the inside to the outside instead of from the outside to the inside.
Motorcycle wheel rims which are made of light-metal alloys and which have so far always been clamped by means of clamping jaws (see European Patent No. 169,255) can also be damaged by the clamping jaws in the case of the larger tire sizes. Moreover, damage of the wheel rim shoulder or the rotating wheel flange of a wheel rim should always be avoided since this can lead to subsequent damage to the new tires being mounted. Moreover, such damage can easily cause the prescribed operating air pressure to drop in an uncontrolled manner.